1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2004 James Cleverdon, IBM.
4 *
5 * Flat APIC subarch code.
6 *
7 * Hacked for x86-64 by James Cleverdon from i386 architecture code by
8 * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
9 * James Cleverdon.
10 */
11 #include <linux/cpumask.h>
12 #include <linux/export.h>
13 #include <linux/acpi.h>
14
15 #include <asm/jailhouse_para.h>
16 #include <asm/apic.h>
17
18 #include "local.h"
19
20 static struct apic apic_physflat;
21 static struct apic apic_flat;
22
23 struct apic *apic __ro_after_init = &apic_flat;
24 EXPORT_SYMBOL_GPL(apic);
25
flat_acpi_madt_oem_check(char * oem_id,char * oem_table_id)26 static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
27 {
28 return 1;
29 }
30
31 /*
32 * Set up the logical destination ID.
33 *
34 * Intel recommends to set DFR, LDR and TPR before enabling
35 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
36 * document number 292116). So here it goes...
37 */
flat_init_apic_ldr(void)38 void flat_init_apic_ldr(void)
39 {
40 unsigned long val;
41 unsigned long num, id;
42
43 num = smp_processor_id();
44 id = 1UL << num;
45 apic_write(APIC_DFR, APIC_DFR_FLAT);
46 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
47 val |= SET_APIC_LOGICAL_ID(id);
48 apic_write(APIC_LDR, val);
49 }
50
_flat_send_IPI_mask(unsigned long mask,int vector)51 static void _flat_send_IPI_mask(unsigned long mask, int vector)
52 {
53 unsigned long flags;
54
55 local_irq_save(flags);
56 __default_send_IPI_dest_field(mask, vector, apic->dest_logical);
57 local_irq_restore(flags);
58 }
59
flat_send_IPI_mask(const struct cpumask * cpumask,int vector)60 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector)
61 {
62 unsigned long mask = cpumask_bits(cpumask)[0];
63
64 _flat_send_IPI_mask(mask, vector);
65 }
66
67 static void
flat_send_IPI_mask_allbutself(const struct cpumask * cpumask,int vector)68 flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector)
69 {
70 unsigned long mask = cpumask_bits(cpumask)[0];
71 int cpu = smp_processor_id();
72
73 if (cpu < BITS_PER_LONG)
74 __clear_bit(cpu, &mask);
75
76 _flat_send_IPI_mask(mask, vector);
77 }
78
flat_get_apic_id(unsigned long x)79 static unsigned int flat_get_apic_id(unsigned long x)
80 {
81 return (x >> 24) & 0xFF;
82 }
83
set_apic_id(unsigned int id)84 static u32 set_apic_id(unsigned int id)
85 {
86 return (id & 0xFF) << 24;
87 }
88
read_xapic_id(void)89 static unsigned int read_xapic_id(void)
90 {
91 return flat_get_apic_id(apic_read(APIC_ID));
92 }
93
flat_apic_id_registered(void)94 static int flat_apic_id_registered(void)
95 {
96 return physid_isset(read_xapic_id(), phys_cpu_present_map);
97 }
98
flat_phys_pkg_id(int initial_apic_id,int index_msb)99 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
100 {
101 return initial_apic_id >> index_msb;
102 }
103
flat_probe(void)104 static int flat_probe(void)
105 {
106 return 1;
107 }
108
109 static struct apic apic_flat __ro_after_init = {
110 .name = "flat",
111 .probe = flat_probe,
112 .acpi_madt_oem_check = flat_acpi_madt_oem_check,
113 .apic_id_valid = default_apic_id_valid,
114 .apic_id_registered = flat_apic_id_registered,
115
116 .irq_delivery_mode = dest_Fixed,
117 .irq_dest_mode = 1, /* logical */
118
119 .disable_esr = 0,
120 .dest_logical = APIC_DEST_LOGICAL,
121 .check_apicid_used = NULL,
122
123 .init_apic_ldr = flat_init_apic_ldr,
124
125 .ioapic_phys_id_map = NULL,
126 .setup_apic_routing = NULL,
127 .cpu_present_to_apicid = default_cpu_present_to_apicid,
128 .apicid_to_cpu_present = NULL,
129 .check_phys_apicid_present = default_check_phys_apicid_present,
130 .phys_pkg_id = flat_phys_pkg_id,
131
132 .get_apic_id = flat_get_apic_id,
133 .set_apic_id = set_apic_id,
134
135 .calc_dest_apicid = apic_flat_calc_apicid,
136
137 .send_IPI = default_send_IPI_single,
138 .send_IPI_mask = flat_send_IPI_mask,
139 .send_IPI_mask_allbutself = flat_send_IPI_mask_allbutself,
140 .send_IPI_allbutself = default_send_IPI_allbutself,
141 .send_IPI_all = default_send_IPI_all,
142 .send_IPI_self = default_send_IPI_self,
143
144 .inquire_remote_apic = default_inquire_remote_apic,
145
146 .read = native_apic_mem_read,
147 .write = native_apic_mem_write,
148 .eoi_write = native_apic_mem_write,
149 .icr_read = native_apic_icr_read,
150 .icr_write = native_apic_icr_write,
151 .wait_icr_idle = native_apic_wait_icr_idle,
152 .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
153 };
154
155 /*
156 * Physflat mode is used when there are more than 8 CPUs on a system.
157 * We cannot use logical delivery in this case because the mask
158 * overflows, so use physical mode.
159 */
physflat_acpi_madt_oem_check(char * oem_id,char * oem_table_id)160 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
161 {
162 #ifdef CONFIG_ACPI
163 /*
164 * Quirk: some x86_64 machines can only use physical APIC mode
165 * regardless of how many processors are present (x86_64 ES7000
166 * is an example).
167 */
168 if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
169 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
170 printk(KERN_DEBUG "system APIC only can use physical flat");
171 return 1;
172 }
173
174 if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
175 printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
176 return 1;
177 }
178 #endif
179
180 return 0;
181 }
182
physflat_init_apic_ldr(void)183 static void physflat_init_apic_ldr(void)
184 {
185 /*
186 * LDR and DFR are not involved in physflat mode, rather:
187 * "In physical destination mode, the destination processor is
188 * specified by its local APIC ID [...]." (Intel SDM, 10.6.2.1)
189 */
190 }
191
physflat_probe(void)192 static int physflat_probe(void)
193 {
194 if (apic == &apic_physflat || num_possible_cpus() > 8 ||
195 jailhouse_paravirt())
196 return 1;
197
198 return 0;
199 }
200
201 static struct apic apic_physflat __ro_after_init = {
202
203 .name = "physical flat",
204 .probe = physflat_probe,
205 .acpi_madt_oem_check = physflat_acpi_madt_oem_check,
206 .apic_id_valid = default_apic_id_valid,
207 .apic_id_registered = flat_apic_id_registered,
208
209 .irq_delivery_mode = dest_Fixed,
210 .irq_dest_mode = 0, /* physical */
211
212 .disable_esr = 0,
213 .dest_logical = 0,
214 .check_apicid_used = NULL,
215
216 .init_apic_ldr = physflat_init_apic_ldr,
217
218 .ioapic_phys_id_map = NULL,
219 .setup_apic_routing = NULL,
220 .cpu_present_to_apicid = default_cpu_present_to_apicid,
221 .apicid_to_cpu_present = NULL,
222 .check_phys_apicid_present = default_check_phys_apicid_present,
223 .phys_pkg_id = flat_phys_pkg_id,
224
225 .get_apic_id = flat_get_apic_id,
226 .set_apic_id = set_apic_id,
227
228 .calc_dest_apicid = apic_default_calc_apicid,
229
230 .send_IPI = default_send_IPI_single_phys,
231 .send_IPI_mask = default_send_IPI_mask_sequence_phys,
232 .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_phys,
233 .send_IPI_allbutself = default_send_IPI_allbutself,
234 .send_IPI_all = default_send_IPI_all,
235 .send_IPI_self = default_send_IPI_self,
236
237 .inquire_remote_apic = default_inquire_remote_apic,
238
239 .read = native_apic_mem_read,
240 .write = native_apic_mem_write,
241 .eoi_write = native_apic_mem_write,
242 .icr_read = native_apic_icr_read,
243 .icr_write = native_apic_icr_write,
244 .wait_icr_idle = native_apic_wait_icr_idle,
245 .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
246 };
247
248 /*
249 * We need to check for physflat first, so this order is important.
250 */
251 apic_drivers(apic_physflat, apic_flat);
252